May 2000

BY KEVIN MAYER

Go Right To:
Next-Gen Network News
The End-To-End Solution
Media Gateways Mean Stepwise Evolution
Decomposition Feeds Growth
The Carrier-Class Gateway, Defined

Perhaps decomposition is an unfortunate word, for the uses we would now assign it. On the other hand, it may be more appropriate than anyone might have guessed. Consider that dwelling on the macabre can be entertaining. Pulse-quickening. Even life-affirming. How can this be? Just possibly, the fascination with the macabre relates to the sense of wonder we may feel when contemplating nature's cycles of decay and renewal.

Analogously, in the world of networking, a decomposition trend could be understood as part of a larger cycle. A phase of disintegration that ultimate leads to new, unprecedented integrations, untold syntheses needing but a glimpse of sun to thrive. To make the analogy clearer, we need consider but a few details. For example, in next-generation networks, decomposition refers to the splitting off of functionality from proprietary, monolithic switches. Such switches typically include a line interface, a trunk interface, a signaling interface, call control, a time slot interchange, and an internal communications bus. However, within an open (or decomposed) architecture, these components, or their functional equivalents, needn't occupy a single box. Instead, they may be distributed over a packet-based network. Various devices could be attached to an IP backbone, and might include media gateways, some form of gateway control, softswitches, and signaling gateways.

The question, however, is why allow such dissolution? Why not keep the traditional network on life support, and forestall the inevitable decay? One reason is that decomposition would expose discrete functional components to innovation and elaboration, possibly by a proliferation of third parties.

Another reason is that a decomposed network could more easily accommodate access-independent telephony. That is, premises or residences relying on different forms of access -- DSL, cable, fixed wireless -- could ultimately connect to packet backbone networks populated by multiple service providers, including telephony application services providers.

Decomposition, then, isn't just about a proliferation of boxes, or a celebration of dissolution for its own sake. Rather, it's about breaking down vertically oriented infrastructures to accommodate horizontally oriented infrastructures, resulting in converged networks that represent a new synthesis, one based less on the logic of traditional, circuit-switched telephony, and more on the logic of the Internet.

Next-Gen Network News

• Clarent Triples Carrier Gateway Port Density
• ipVerse Launches Open Softswitch Alliance
• Cirilium Announces Power~Suite
• NMS CG 6000C First In New Product Family

Clarent Triples Carrier Gateway Port Density
Clarent Corporation has announced a new higher density gateway: the Clarent Carrier Gateway 1200, a high-capacity Internet telephony gateway for connecting voice, fax, and data calls over TCP/IP networks. The new gateway interacts with the billing, call routing, and network administration in the Clarent Command Center software package. The Carrier Gateway 1200 will support 8, 10, or 12 spans (24 ports/span, T1; 30 ports/span, E1) in a single 5U chassis, allowing service providers to scale their networks with one-third of the footprint previously required.
No. 538, www.comsolmag.com/freeinfo

ipVerse Launches Open Softswitch Alliance
To promote standardization and speed the deployment of enhanced voice and data services, ipVerse announced the formation of the Open Softswitch Alliance (OSA). The initiative has already won the support of several companies. These companies include Copper Mountain Networks, Convergent Networks, General Bandwidth, Iperia, Shoreline Communications, TollBridge Technologies, Trillium Digital Systems, Vertical Networks, and VocalData. OSA partners will cooperate to demonstrate interoperability and engage in joint marketing and sales calls, simplifying vendor selection for service providers, impressing upon them the availability of complete, working solutions, accelerating the migration to next-generation network infrastructures.
No. 539, www.comsolmag.com/freeinfo

Cirilium Announces Power~Suite
Cirilium has announced the availability of its Power~Suite integrated carrier-class IP telephony solution. Power~Suite complies with both H.323 and MGCP standards and is interoperable with Cisco's voice and data routers. The Power~Suite solution consists of two main components: the Cirilium Media Gateway and the Cirilium NetControl Center. "With the release of Power~Suite, we begin to fulfill the promise inherent in Cirilium of integrating our core voice and data competencies to the advantage of our customers," said CEO Tom Parise. "In doing so, we have dramatically expanded our horizons beyond niche application providers to encompass the most aggressive ISPs, CLECs, and other next-gen telcos."
No. 540, www.comsolmag.com/freeinfo

NMS CG 6000C First In New Product Family
Natural MicroSystems has released the first product in their new Convergence Generation (CG) carrier-class cPCI-based family. The CG 6000C offers 240 VoIP ports per CompactPCI slot; hosts Fusion 4.0, NMS's VoIP software platform; and is also supported by the Natural Access development and runtime environment. The cPCI form factor allows service providers to hot-swap cards while systems remain running, making this an attractive platform for the development of next-gen, IP-based enhanced services. Also, developers may take advantage of the platform's pre-built templates, which free carriers from having to recreate the most common configurations.
No. 541, www.comsolmag.com/freeinfo

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BY STEVE BAECHLE

On the hunch that the whole will be greater than the sum of its parts, leading IP telephony carrier infrastructure suppliers are broadening (and integrating) their offerings, hoping to attract carrier customers with end-to-end solutions that consolidate maintenance efforts and reduce costs.

NO END OF APPROACHES
As part of this trend, infrastructure suppliers are demonstrating greater awareness of carriers' business requirements, such as clearinghouse and settlement services. To take on broader challenges, infrastructure suppliers are taking different approaches: some suppliers rely on partnering; some resell third-party solutions; some accelerate internal development.

Already, PC-based gateways are migrating to standalone hardware-based systems to achieve carrier-class reliability. And these systems are quickly matching traditional voice networks in reliability and scalability. In addition, makers of hardware-based systems are focusing on software, and on rounding out back-end solution components with software-based feature creation platforms.

THE END GAME
While different suppliers take different approaches towards assembling end-to-end solutions, the ultimate result -- if it is to be competitive -- must include the following key components:

• Carrier-Class Media Gateways: Here, the trend is towards chassis-based, inherently redundant architectures with superior scalability.
• Signaling Gateways: The media gateway will be fully integrated with signaling gateways for IP, ATM, and TDM networks, with call agents supporting SS7, H.323, MGCP, and other signaling types.
• Gatekeepers: Tight integration between gateways and gatekeepers will strengthen carriers' competitive advantage as they expand into new territory and pass traffic to other providers with varying architectures.
• Centralized Intelligence, Distributed Applications: Much of the intelligence resident in the IP telephony network today will shift towards centralized platforms. The models for H.323, SIP, etc. are all based on this premise. However, the applications which run on the IP telephony network will become more distributed.
• Back-Office Components: Expanding on traditional pre- and post-paid billing platforms, the back-office must expand to round out carrier infrastructures with fully integrated call accounting, clearinghouse capabilities, and billing and settlement functions. Roaming and settlement must be locked in so carriers can seamlessly pass calls between their respective networks -- and get paid for it.

THE END IS THE BEGINNING
As IP telephony achieves mass acceptance, users will begin to see its limitless potential for value-added features. In turn, service providers will race to become known as the most accommodating, the best and fastest provider with the greatest functionality.

In anticipation of the demands that IP telephony's acceptance will surely stimulate, the vendor community is pulling together the components needed to help carriers roll out new capabilities, serve new markets, and institute new pricing structures virtually at will. However, one-stop shopping for its own sake won't suffice. To satisfy carriers, suppliers will have to represent both the single-source supplier and the best-of-breed supplier -- all at the same time.

Steve Baechle is vice president of Business Development for Cirilium Corporation. For more information, visit www.cirilum.com.

BY DOUGLASS FROSST

If you're a service provider looking to evolve your proprietary, localized network to one that is distributed and capable of offering new, revenue-generating services, then you'll want to examine media gateways. Why? Because media gateways provide a stepwise evolution from the Old World (circuit-based networks) to the New World (distributed, packet-based networks).

Media gateways unburden circuit-switched networks and enable instant delivery of valued-added IP services. How, you ask? In three steps:

1. In a typical localized network, the Class 5 switch is handling both standard voice and data modem calls -- the latter having much longer call hold-times that result in significant switch congestion. Using a media gateway, you can offload the data modem calls from the circuit network and divert them directly onto an efficient packet network. Once installed, the media gateway will identify the ISP phone numbers and switch those calls directly to the ISP's network access servers, leaving the Class 5 switch to handle the voice calls that it was designed for. This is a win/win for the service provider, who gets more TDM capacity though an investment in a packet solution.
2. As the ISP data traffic grows, additional capacity is added only on the media gateway, at a significant savings over typical TDM switches. Additionally, media gateways are capable of carrier packet voice services. With the gateway in place, these services can be introduced at the appropriate time to take advantage of lower-cost packet transport availability, or higher-revenue packet-based service opportunities. This enables new revenue streams and operating cost reductions, taking advantage of the lower-cost packet voice infrastructure.
3. With additional distributed media gateways in your network, you can now create a new set of packet services, such as unified communications, for long-term growth and profitability. Additional investment in the circuit network is no longer required as the traffic migrates to the higher-revenue, lower-cost packet infrastructure.

Douglas Frosst is manager of Product Marketing for Cisco Systems. The Cisco media gateway, the Cisco MGX 8260, was recently announced. For more information, visit www.cisco.com.

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BY DAVID FRIDLEY

When is a gateway said to be ... decomposed? Well, this distinction is reserved for those gateways that treat call setup and teardown (also called call signaling) apart from real-time data transport (the voice). When these two functions are separated, it is possible to build systems that are larger and more flexible than systems relying on traditional VoIP gateways.

SEPARATING FUNCTIONALITY WITHIN A CHASSIS
One way to separate transport and signaling is to allocate them to DSP and host resources, respectively. For example, a DSP resource card may be used to handle all aspects of the real-time data transport. Voice and fax calls enter the board through the T1/E1 interface. Then, the calls are compressed (or demodulated), packetized, and transmitted out an embedded 100-Mbit Ethernet interface.

However, when a "ring" signal arrives from the T1 interface, the signal is sent up to the host. Then, the host signals the far-end gateway, or VoIP terminal, through it's own Ethernet interface. When the call is answered, the real-time data connections are made between the resource board and the far-end gateway or terminal. This separation allows VoIP gateways to grow by accommodating more resource boards.

DIVIDING FUNCTIONALITY BETWEEN CHASSIS
Another way to divide transport and signaling is with a new protocol called the Media Gateway Control Protocol (MGCP). With MGCP, call control and real-time transport are handled by separate chassis communicating through IP networks. In this paradigm, the real-time transport system is called a media gateway, and the call signaling system is called the media gateway controller.

What's exciting about this new paradigm is that it allows applications to be built on generic server platforms using standard network protocols that utilize voice and fax resources on media gateway systems. For example, a VoIP-enabled enterprise telephone system can be built using media gateways and a PC.

The media gateway's T1 interface is connected to a provisioned T1 from the local service provider. Its IP side is connected to the enterprise's main IP backbone. And every desk is equipped with an IP phone or a PC running a VoIP terminal client.

When a call comes into the media gateway over the PSTN, the PBX application on the PC is signaled. The PC determines which desktop system should receive the call, and then signals the desktop terminal and the media gateway to establish real-time transport sessions. In this architecture, the PBX application runs on a generic system, and the system can be expanded by simply attaching more media gateways to the networks.

AND NOW, THE GROWTH
As we've seen, decomposition of the gateway allows for much larger VoIP systems. Within a chassis, more boards may be accommodated. Or, within an MGCP-compatible network, more chassis may be accommodated. Either way, decomposition provides more flexibility in the development of applications. With decomposed gateways, developers are better able to keep pace with the market's rapid growth and continuing evolution of features.

David Fridley is director of marketing for Anatel Communications, an Analogic Company. The author welcomes e-mail at [email protected].

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BY JOSH BENVENISTE

We're hearing a lot about the new wave of carrier-class offerings. We're hearing that one of these offerings, the carrier-class gateway, embodies increased density, intelligence, and availability, enabling carriers to offer a high-quality, reliable IP telephony service. We're hearing that IP telephony effectively provides carriers a toll-quality means of passing voice traffic over the Internet, and that next-generation gateways are being used instead of Class 4 switches for long-haul traffic transport.

But what makes carrier-class gateways capable of fulfilling all these roles? What is it about carrier-class gateways that enables them to provision thousands of customers -- and to do so quickly, easily, and cost-effectively? What qualifies carrier-class gateways for deployment in carrier networks?

If it is to be considered carrier class, a gateway must include toll-quality voice, scalability to thousands of calls, and full redundancy -- including fault-tolerance, hot swapability, and PSTN fallback. Also, a gateway must easily communicate with a back-end management system, which provides for user validation, rating, billing, accounting, routing, registration of users, management of overall service, and more.

Since the gateway is to provide seamless connection between the Internet and PSTN, standards and interoperability support is also critical to any carrier implementation. Interoperability with H.323 products and SS7/C7 networks are a must. Another essential for a carrier-class gateway is support for voice compression standards -- namely, G.723.1, G.729a, and T.38 for real-time fax over IP networks.

Josh Benveniste is marketing manager for Clarent Corporation. For more information, please visit their Web site at clarent.com.

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